Study Evaluating SARS-CoV-2 (COVID-19) Humoral Response After BNT162b2 Vaccine in Immunocompromised Adults Compared to Healthy Adults

The serious, even fatal, forms of COVID-19 preferentially affect elderly and fragile subjects. Among these populations at risk, people who are immunocompromised (either by a disease and / or its treatment) have a theoretical risk of responding less well to a preventive vaccination.

The main objective of this study aims to compare the vaccine response of immunocompromised people with healthy subjects (non-immunocompromised), i.e. to assess the serum humoral response (titre and neutralizing capacity of the antibodies induced) following vaccination with ComirnatyTM (i.e. BNT162b2, an anti-SARS-CoV-2 vaccine from Pfizer BioNTech) in immunocompromised persons in comparison to healthy subjects (non-immunocompromised).

Secondary objectives are as follows:

• To evaluate the antibody response in the nasal mucosa (titre and neutralizing capacity of the antibodies induced, collected by means of a nasopharyngeal swab) following vaccination with ComirnatyTM in immunocompromised people as compared to healthy subjects (vaccinated either with two doses of ComirnatyTM or, in a subgroup, with one dose of Astra Zeneca's VaxzeriaTM followed by one dose of ComirnatyTM).
• Evaluate the serum and mucosal antibody response (titre and neutralizing capacity of the antibodies induced) against emerging strains of SARS-CoV-2 (so-called Alpha, Beta, Gamma, Delta strains).
• Evaluate the post-vaccination clinical protection against the risk of COVID-19 infection (incident cases after vaccination).

Inclusion criteria

• Adult volunteers to be vaccinated with the ComirnatyTM vaccine and to participate in the study, belonging to one of the following groups:

• Group of immunocompromised (15 participants per immunosuppression subgroup):

• Kidney transplant
• Extracorporeal dialysis
• Solid cancer under chemotherapy and / or radiotherapy
• Myeloma under chemotherapy
• Hematologic malignancies under chemotherapy
• Diseases treated with anti CD20 (or patients not treated at the time of the vaccine but who will be immediately after)
• Multiple sclerosis under anti CD20 (or patients not treated at the time of the vaccine but who will be immediately after)
• Common variable immune deficiency or other causes of severe hypogammaglobulinemia requiring chronic treatment with polyvalent immunoglobulin
• Malignant tumor under anti-PD1 or anti-PDL1
• People living with HIV
• Complicated type 2 diabetes (with micro and / or macroangiopathy)
• Group of non-immunocompromised subjects (controls, n = 75)

• 60 people vaccinated with the ComirnatyTM
• 15 people vaccinated with Astra Zeneca's VaxzevriaTM for the first dose

Exclusion criteria

• Minors
• Pregnant or breastfeeding women
• Persons under tutorship or curatorship
• Protected adults
• Person under legal protection
• Person not affiliated to a social security scheme
• People with a contraindication to receiving the ComirnatyTM vaccine
• People who have already been vaccinated against SARS-CoV-2

Note: a history of COVID-19 (> at 3 months) is not a contraindication to vaccination and is therefore not a criterion for non-inclusion in the study.